diff --git a/lib/rds_decoder_redsea_impl.cc b/lib/rds_decoder_redsea_impl.cc
index f385a73..63c9b55 100644
--- a/lib/rds_decoder_redsea_impl.cc
+++ b/lib/rds_decoder_redsea_impl.cc
@@ -293,33 +293,36 @@ int rds_decoder_redsea_impl::work (int noutput_items,
                                         checkword=reg & 0x3ff;//checkword part of received block (lower 10 bits)
 /* manage special case of C or C' offset word */
                                         if (block_number==2) {
-                                                if (variant==0){//A
-                                                    offset_char = 'C';
-                                                    block_received_crc=checkword^offset_word[2];
-                                                }
-                                                else{//B
-                                                    offset_char = 'c';
-                                                    block_received_crc=checkword^offset_word[4];
-                                                    //dout<<"B"<<std::endl;
-                                                }
-                                                if (block_received_crc==block_calculated_crc) {
-                                                        good_block=true;
-                                                }else{
-                                                    //try correcting:
-                                                    uint32_t corrected_block= correctBurstErrors(reg,offset_char);
-                                                    if(corrected_block != reg){
+                                                if (variant == 2 ) dout << "error: 3rd block received before 2nd"<<std::endl;
+                                                else{
+                                                    if (variant==0){//A
+                                                        offset_char = 'C';
+                                                        block_received_crc=checkword^offset_word[2];
+                                                    }
+                                                    else{//B
+                                                        offset_char = 'c';
+                                                        block_received_crc=checkword^offset_word[4];
+                                                        //dout<<"B"<<std::endl;
+                                                    }
+                                                    if (block_received_crc==block_calculated_crc) {
                                                             good_block=true;
-                                                            block_was_corrected=true;
-                                                            group_corrected_blocks_counter++;
-                                                            //wrong_blocks_counter++;
-                                                            dataword=(corrected_block>>10) & 0xffff;
-                                                            checkword=corrected_block & 0x3ff;
-                                                            
-                                                            
-                                                            //dout << "corrected error"<<std::endl;
-                                                    }else {
-                                                                  wrong_blocks_counter++;
-                                                                  good_block=false;
+                                                    }else{
+                                                        //try correcting:
+                                                        uint32_t corrected_block= correctBurstErrors(reg,offset_char);
+                                                        if(corrected_block != reg){
+                                                                good_block=true;
+                                                                block_was_corrected=true;
+                                                                group_corrected_blocks_counter++;
+                                                                //wrong_blocks_counter++;
+                                                                dataword=(corrected_block>>10) & 0xffff;
+                                                                checkword=corrected_block & 0x3ff;
+                                                                
+                                                                
+                                                                //dout << "corrected error"<<std::endl;
+                                                        }else {
+                                                                      wrong_blocks_counter++;
+                                                                      good_block=false;
+                                                        }
                                                     }
                                                 }
 
@@ -327,8 +330,6 @@ int rds_decoder_redsea_impl::work (int noutput_items,
                                         else {
                                                 block_received_crc=checkword^offset_word[block_number];
                                                 if (block_received_crc==block_calculated_crc) {//valid block
-                                                        if (block_number==0)
-                                                          last_pi=dataword;
                                                         good_block=true;
                                                         offset_char=expected_offset_char[block_number]; //expected_offset_char[]={'A','B','?','D'};
                                                         /*if (block_number==0) offset_char = 'A';
@@ -380,10 +381,12 @@ int rds_decoder_redsea_impl::work (int noutput_items,
                                         }
 /* done checking CRC */                 
                                         if (block_number==0 && good_block) {
+                                                last_pi=dataword;
                                                 group_assembly_started=true;
                                                 //group_corrected_blocks_counter=block_was_corrected;
                                                 group_corrected_blocks_counter=0;
                                                 group_good_blocks_counter=1;
+                                                variant=2;
                                         }
                                         if (block_number==1 && good_block) {//2nd block - > read group type variant
                                                 variant=(dataword>>11)& 0x1;
@@ -406,6 +409,7 @@ int rds_decoder_redsea_impl::work (int noutput_items,
                                                         group_good_blocks_counter++;
                                                 }
                                                 if (group_good_blocks_counter==5) decode_group(group);
+                                                //if (group_good_blocks_counter==5 and group_corrected_blocks_counter>0) decode_group(group);//test corrected blocks
                                         }
                                         block_bit_counter=0;
                                         block_number=(block_number+1) % 4;
diff --git a/python/tmc_classes.py b/python/tmc_classes.py
index 1ca13b7..e7c8829 100644
--- a/python/tmc_classes.py
+++ b/python/tmc_classes.py
@@ -428,7 +428,7 @@ class tmc_location:
             print("lcn is segment  %i"%lcn)
           elif self.lcl_obj.roads.has_key(lcn) and self.tableobj.debug: 
             print("lcn is road  %i"%lcn)
-          else:
+          elif self.tableobj.debug:
             print("lcn not found  %i"%lcn)
           
         elif self.tableobj.log or self.tableobj.debug:
diff --git a/python/tmc_parser.py b/python/tmc_parser.py
index 9c96170..58ddac8 100644
--- a/python/tmc_parser.py
+++ b/python/tmc_parser.py
@@ -100,7 +100,7 @@ class tmc_parser(gr.sync_block):
         print("closing tmc display")
     def save_data(self):
         print_dbg('saving data..', end="")
-        self.dataLock.acquire(1)
+        #self.dataLock.acquire(1) #disabled 2017-06-06 for performance
         if self.writeDB:
             self.dbLock.acquire(1)
             self.db.commit()
@@ -108,7 +108,7 @@ class tmc_parser(gr.sync_block):
         f=open(self.workdir+'google_maps_markers.js', 'w')
         
         markerstring=self.tmc_messages.getMarkerString()
-        self.dataLock.release(1)
+        #self.dataLock.release(1)
         markerstring+='\n console.log("loaded "+markers.length+" markers")'
         markerstring+='\n document.getElementById("errorid").innerHTML = "loaded "+markers.length+" markers";'
         f.write(markerstring)
@@ -287,7 +287,7 @@ class tmc_parser(gr.sync_block):
                     pass
         return return_string
 def print_dbg(message,end="\n"):
-  dbg=True
+  dbg=False
   if dbg:
     print(message,end=end)
 class tmc_parser_Widget(QtGui.QWidget):